Centrifugal gradient dialysate dual-chamber hemodiafiltrator

Abstract

The present invention provides a hemodiafiltrator comprising two compartmentalized dialysate chambers coaxially arranged in tandem. A single packed bundle of hollow fibers for blood flow is enclosed coaxially along a longitudinal axis inside the dual dialysate chambers. A configuration of a tandem arrangement of the dual dialysate chambers at least comprises a first dialysate chamber for an acidic dialysate with a varying level of urea and a second compartmentalized dialysate chamber for a basic dialysate with no urea but with a level of ammonia up to a level detected in normal human blood.

What is claimed is: 
     
       1. A centrifugal gradient dialysate dual-chamber hemodiafiltrator for hemodiafiltration, comprising:
 a blood compartment enclosed in a compartmentalized tubular cylinder, comprising a packed bundle of hollow fibers having an open central tubular column in a doughnut configuration on a radial cross-section; 
 wherein the open central tubular column is compartmentalized into a proximal portion and a distal portion by a coaxial cone disk radially occluding a portion of the open central tubular column; 
 the compartmentalized tubular cylinder, comprising a first dialysate conduit, a mid dialysate tubular cylinder and a second dialysate conduit; 
 wherein an inner circumferential rim protruding from an inner tubular wall of the mid dialysate tubular cylinder divides the mid dialysate tubular cylinder into a proximal portion of the mid dialysate tubular cylinder and a distal portion of the mid dialysate tubular cylinder; 
 wherein the first dialysate conduit distally adjoins the proximal portion of the mid tubular cylinder and the second dialysate conduit proximally adjoins the distal portion of the mid tubular cylinder; and 
 wherein the first dialysate conduit and the second dialysate conduit are provided in a coaxial tube-in-tube configuration with a first outer conical reservoir conduit coaxially enclosing a first inner longitudinal tubular conduit and with a second outer conical reservoir conduit coaxially enclosing a second inner longitudinal tubular conduit, respectively; 
 wherein there is provided a longitudinal distance of at least 1 mm between the inner circumferential rim and the coaxial cone disk on a longitudinal axis of the compartmentalized tubular cylinder; 
 the blood compartment comprising a proximal blood chamber and a distal blood chamber; 
 wherein a roof portion of the proximal blood chamber proximally adjoins a base of the first dialysate conduit; 
 wherein the proximal blood chamber is connected to a blood intake tube; 
 wherein a roof portion of the distal blood chamber distally adjoins a base of the second dialysate conduit; 
 wherein the distal blood chamber is connected to a blood output tube; and 
 wherein a proximal portion and a distal portion of the packed bundle of hollow fibers for blood flow of the blood compartment are coaxially and leakproofly connected to the proximal blood chamber and the distal blood chamber, respectively; and 
 the proximal portion and the distal portion of the open central tubular column of the packed bundle of the hollow fibers are leakproofly and coaxially connected to the first inner longitudinal tubular conduit and the second inner longitudinal tubular conduit, respectively; 
 wherein the first dialysate conduit is configured to take a first dialysate distally through the first inner longitudinal tubular conduit in the proximal portion of the open central tubular column, and to drain the first dialysate proximally through the first outer conical reservoir conduit; and 
 wherein the second dialysate conduit is configured to take a second dialysate proximally through the second inner longitudinal tubular conduit in the distal portion of the open central tubular column, and to drain the second dialysate distally through the second outer conical reservoir conduit. 
 
     
     
       2. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the compartmentalized tubular cylinder further comprises:
 the coaxial cone disk radially occluding the portion of the open central tubular column; 
 wherein the coaxial cone disk comprises an outer conical surface distally facing the distal portion of the open central tubular column; and 
 wherein the coaxial cone disk comprises an inner conical depression proximally facing the proximal portion of the open central tubular column. 
 
     
     
       3. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 2 , wherein the coaxial cone disk further comprises:
 wherein the coaxial cone disk radially occludes the portion of the open central tubular column so as to allow a first dialysate to flow toward the inner conical depression of the coaxial cone disk in a proximal-to-distal direction in the proximal portion of the open central tubular column; 
 wherein the coaxial cone disk radially occludes the portion of the open central tubular column so as to allow a second dialysate to flow toward the outer conical surface of the coaxial cone disk in a distal-to-proximal direction in the distal portion of the open central tubular column; and 
 wherein the first dialysate flows in a coaxially opposite direction to the second dialysate. 
 
     
     
       4. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 2 , wherein the coaxial cone disk further comprises:
 the outer conical surface distally facing toward the distal portion of the open central tubular column; 
 wherein the outer conical surface is configured to deflect off at a plurality of obtuse angles the second dialysate axially flowing in the distal-to-proximal direction from the distal portion of the open central tubular column to the outer conical surface of the coaxial cone disk. 
 
     
     
       5. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 2 , wherein the coaxial cone disk further comprises:
 the inner conical depression proximally facing the proximal portion of the open central tubular column; 
 wherein the inner conical depression is configured to deflect off at a plurality of acute angles the first dialysate axially flowing in the proximal-to-distal direction from the proximal portion of the open central tubular column to the inner conical depression. 
 
     
     
       6. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 2 , wherein the coaxial cone disk further comprises:
 the outer conical surface of the coaxial cone disk; 
 wherein the outer conical surface of the coaxial cone disk is configured deflect off a second dialysate so as to direct the second dialysate from the distal-to-proximal direction in the distal portion of the open central tubular column to the proximal-to-distal direction in the distal portion of an outer circumferential space of the mid dialysate tubular cylinder. 
 
     
     
       7. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 2 , wherein the coaxial cone disk further comprises:
 the inner conical depression of the coaxial cone disk; 
 wherein the inner conical depression of the coaxial cone disk is configured to deflect off a first dialysate so as to direct a first portion of the first dialysate from the proximal-to-distal direction in the proximal portion of the open central tubular column to the distal-to-proximal direction in the proximal portion of an outer circumferential space of the mid dialysate tubular cylinder; and 
 wherein the inner conical depression of the coaxial cone disk is configured to deflect off a first dialysate so as to direct a second portion of the first dialysate from the proximal-to-distal direction in the proximal portion of the open central tubular column to the proximal-to-distal direction in the distal portion of an outer circumferential space of the mid dialysate tubular cylinder. 
 
     
     
       8. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the mid dialysate tubular cylinder further comprises:
 the proximal portion of the mid dialysate tubular cylinder proximally opens to the first outer conical reservoir conduit through a plurality of proximal curvilinear fenestrations disposed thereof around an outer perimeter of an upper radial wall of the mid dialysate tubular cylinder, so as to flow the first dialysate from the proximal portion of the mid dialysate tubular cylinder through the plurality of the proximal curvilinear fenestrations in the distal-to-proximal direction to the first outer conical reservoir conduit. 
 
     
     
       9. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the mid dialysate tubular cylinder further comprises:
 the distal portion of the mid dialysate tubular cylinder distally opens to the second outer conical reservoir conduit through a plurality of distal curvilinear fenestrations disposed thereof around an outer perimeter of a lower radial wall of the mid dialysate tubular cylinder, so as to flow the second dialysate from the distal portion of the mid dialysate tubular cylinder through the plurality of the distal curvilinear fenestrations in the proximal-to-distal direction to the second outer conical reservoir conduit. 
 
     
     
       10. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the mid dialysate tubular cylinder further comprises:
 an outer circumferential space, provided in a cylindrically tubular configuration, disposed thereof between an outer peripheral layer of the packed bundle of the hollow fibers and the inner tubular wall of the mid dialysate tubular cylinder; 
 wherein the outer circumferential space is compartmentalized by the inner circumferential rim into a proximal portion of the outer circumferential space and a distal portion of the outer circumferential space; 
 wherein the proximal portion of the outer circumferential space proximally opens to the first outer conical reservoir through the plurality of the proximal curvilinear fenestrations; 
 wherein the proximal portion of the outer circumferential space is configured to transmit the first dialysate to the first outer conical reservoir conduit through the plurality of the proximal curvilinear fenestrations; 
 wherein the distal portion of the outer circumferential space distally opens to the second outer conical reservoir through the plurality of the distal curvilinear fenestrations; and 
 wherein the distal portion of the outer circumferential space is configured to transmit the second dialysate to the second outer reservoir conduit through the plurality of the distal curvilinear fenestrations. 
 
     
     
       11. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the mid dialysate tubular cylinder further comprises:
 a plurality of proximal curvilinear fenestrations circumferentially encircle the roof portion of the proximal blood chamber; and 
 a plurality of distal curvilinear fenestrations circumferentially encircle the roof portion of the distal blood chamber. 
 
     
     
       12. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the proximal blood chamber further comprises:
 a proximal inner coaxial tubular cylinder coaxially disposed in the proximal blood chamber; 
 wherein the proximal inner coaxial tubular cylinder compartmentalizes the proximal blood chamber into a proximal outer tubular columnar space outside of the proximal inner coaxial tubular cylinder and a proximal inner tubular columnar space inside the proximal inner coaxial tubular cylinder; 
 wherein the proximal outer tubular columnar space fixedly encases the proximal portion of the packed bundle of the hollow fibers; 
 wherein the proximal inner coaxial tubular cylinder proximally adjoins the first inner longitudinal tubular conduit, and is distally inserted in the proximal portion of the open central tubular column; and 
 wherein the proximal inner coaxial tubular cylinder is configured to distally transmit the first dialysate from the first inner longitudinal tubular conduit to the proximal portion of the open central tubular column. 
 
     
     
       13. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the distal blood chamber further comprises:
 a distal inner coaxial tubular cylinder coaxially disposed in the distal blood chamber; 
 wherein the distal inner coaxial tubular cylinder compartmentalizes the distal blood chamber into a distal outer tubular columnar space outside of the distal inner coaxial tubular cylinder and a distal inner tubular columnar space inside the distal inner coaxial tubular cylinder; 
 wherein the distal outer tubular columnar space fixedly encases the distal portion of the packed bundle of the hollow fibers; 
 wherein the distal inner coaxial tubular cylinder proximally adjoins the second inner longitudinal tubular conduit, and is proximally inserted in the distal portion of the open central tubular column; and 
 wherein the distal inner coaxial tubular cylinder is configured to proximally transmit the second dialysate from the second inner longitudinal tubular conduit to the distal portion of the open central tubular column. 
 
     
     
       14. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the packed bundle of the hollow fibers further comprises:
 an outer peripheral layer of the packed bundle of the hollow fibers; 
 wherein the outer peripheral layer is separated by >1 mm of a radial distance from an inner tubular wall of the mid dialysate tubular cylinder. 
 
     
     
       15. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the packed bundle of the hollow fibers further comprises:
 the open central tubular column coaxially disposed in a central portion of the packed bundle of the hollow fibers along a longitudinal axis of the packed bundle of the hollow fibers; 
 wherein the open central tubular column is supported by an inner string harness in a tubular configuration abuttingly disposed on a perimeter of the open central tubular column. 
 
     
     
       16. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the packed bundle of the hollow fibers further comprises:
 an inner string harness; 
 wherein the coaxial cone disk is fixedly and coaxially attached to a portion of the inner string harness; and 
 wherein the portion of the inner string harness attached to the coaxial cone disk is disposed distally to the inner circumferential rim on the longitudinal axis of the compartmentalized tubular cylinder. 
 
     
     
       17. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the inner circumferential rim further comprises:
 wherein the inner circumferential rim tightly encircles an outer peripheral layer of a portion of the packed bundle of the hollow fibers coaxially disposed inside the mid dialysate tubular cylinder, so as to partition the packed bundle of the hollow fibers into an upper half portion of and a lower half portion of the packed bundle of the hollow fibers; and 
 wherein the inner circumferential rim is disposed proximally to the coaxial cone disk on the longitudinal axis of the compartmentalized tubular cylinder. 
 
     
     
       18. The centrifugal gradient dialysate dual-chamber hemodiafiltrator according to  claim 1 , wherein the mid dialysate tubular cylinder further comprises:
 a proximal portion of the second dialysate chamber, bordered proximally by the inner circumferential rim and distally by the coaxial cone disk; 
 wherein a longitudinal length of the proximal portion of the second dialysate chamber measures as the longitudinal distance between the coaxial cone disk and the inner circumferential rim; and 
 wherein the proximal portion of the second dialysate chamber is configured to simultaneously receive a portion of the first dialysate deflected off an inner conical depression and a portion of a second dialysate deflected off an outer conical surface.